Molecular and Biochemical Characterization of Some Egyptian Genotypes Rhizobium (Vicia Faba) Isolates

Abstract

Thirteen Rhizobial isolates were recovered from the root nodule of Faba bean (Viciae faba L.) grown in different geographic locations and soil properties in Egypt. The tested isolates were identified as R. leguminosarum sv. Viciae on the bases of morphological, biochemical characteristics and sequences of the gene encoding 16s rRNA. Rhizobium isolates were tested for their ability to utilize different carbon sources. Mannitol and Glucose were the best source of carbon. All tested isolates from Vicia faba differ in IAA production. The maximum amount of IAA production was in the range of (2.04 μg/ml) for Al Arish isolate to (7.5 μg/ml) for Ismailia isolate among the studied isolates. A great ability to degrade Roundup herbicide among the tested isolates was observed. Sues City isolate was the best active degrading Roundup herbicide on plates. All of the tested isolates showed resistances to (25 and 50 mg/ml) expect isolate RL7 was sensitive at high Roundup herbicide concentration, while isolates RL5, RL6, RL8, RL10 and RL13 were the most tolerance at 50 mg/ml herbicide. South Sinai, Zefta, Rafah, El-Menia, Cairo and Ismailia isolates shared a common band with mol. wt. of 70 KDa. New protein types were detected due to the differential response of the five isolates to the effects of the environment stress.